Device for correcting clocks for errors of more than one hour



Nov. 22, 1955 D. F. COLE DEVICE FOR CORRECTING CLOCKS FOR ERRORS OF MORETHAN ONE HOUR 3 Sheets-Sheet 1 Filed April 7, 1953 INVENTOR.

DAVID F COLE ATTORNEY Nov. 22, 1955 Filed April 7, 1953 D. F. COLE2,724,233 DEVICE FOR CORRECTING CLOCKS FOR ERRORS OF MORE THAN ONE HOUR5 Sheets-Sheet 2 HG. Z

INVENTOR. DAVID F COLE ATTORNEY D. DEVICE FOR CORRECTING CLOCKS FOR NOV.22, COLE ERRORS OF MORE THAN ONE HOUR 3 Sheets-Sheet 3 Filed April '7,1953 INVENTOR. DAVID F COLE AT TORNEY U ted. S at s P ten ApplicationAipril 7, 1953, Serial Nd. 347,314 11 crisis. (or. 5845;

, Thisinvention relates te-clock, correcting meansof the type which iscapable of bringing a clock to correct time h nl z r o by mo ntqne ho r:,Suche corrscticn means may be capable ,of rnaking a 1-2 hour correctionof a standardclock, for example, or a 24 hourcorrection of a24 hourclock. f Onescheme fortaccomplishing the objective indicated has..been..to correct the cloclcby acting directly on the hours shaft, to bring itto a predetermined hour position, the minutes shaft being revolved oncefor each; hourly advance of the hours shaft, through thet normal;reduction gearing of the clock. Thishas the disadvantage that the resetposition of the minutes handcannot be determined asv exactly. as if theresetting means acts directly on the minutes shaft. H 5 I cco d ly?p siwt.oe s a @839 o ide a ere se t t -11a 9 9 w h will reset the 1, 9. 1;through; a plurality of hours, hut, vvnich yvil l determine the finalreset position by direct action on the minutes shaft J: as? t H 7 fi FaP lY- t m -tha 9. 1s 9 W. onthe hours shat-tend minutesshaft, thgearing between thesetwo. shafts includingslip frieti 1 means. .A e objt s: s fl fo el q; o. t A. fiction m n sm ia 9 with su plstnsmamn anacting through said .hourly. eorrect on :rneans, to correct the clockfor an errorof n orethan one o of the kind last menu means for,making.;corrections of more than one hour is very simple and economical.th rb edth tin i nW. f i s nti n sla ms s si us ra d at th 13.9- i t araw ihs ss c sabrr a sam les the principle of the inventiorr and the best,ode, which has been, contemplated, of applying that principle.

in t qg fi :1 *i": .-Fig. 1 is-a front elev 6 invention, with partshroken awa I J 2. a e. l r an l News ;PQ :9 t e mechanism shown in Fig.1, with the parts in different positiQns- 17:1:15; s1; 42; 1 v Fig. 4 isa section substa ally on the line 44 of 2 s; :tgzrf '2: r if'l'zil 1:151:rui-sz'zirr .Fig. 5 is a detail perspective view of the latch mechamsm.t. v 1.,

1 t di w s ail vt ,54 swafis sra hr wa t q o dary lWKJt W .11 1.generalv construction to the onel. show .lu-l fl 'g 1 }L.Y,. collar 34revolvably mounted on the inner end of shaft 22. The clutch collar 34has an internally toothed socket which receives a pinion 36 driven atthe rate of one revolution perminute through gears 38 and 40 by theshaft 42 of a synchronous motor 44. Gears 3S and 40 are merelydiagrammatic representations of a reduction gearing which provides theproper rate of revolution of the pinion36., n,- The seconds shaft 22drives, the minutes shaft, 24 through a conventional. gear trainconsisting of gears 46, 48 and 50. The latter gear turns at the rate ofonerevolution per hour, its rotation -being-transmitted through a springspider 52 to a gear 54 rigidly, fixed to the minutes shaft 24. In asimilar way the hours shaft is driven from the minutes shaft throughgearing consisting of the gears 56, 58, 60, the latter being rigidlyfixed to the hours shaft An idler gear 62. meshing with the pinion 36drives another pinion 64 rigidly fixed to aserrateddisc 66, called thereset drive ratchet. This disc rotates continuously at the rate of onerevolution per minute on ashaft 68. Coaxialwith the reset drive ratchet66, and ,mounted omits same-shaft 68, is a stop disc 70. A clutch dog 72pivotally mounted at 74 on the disc 70 hasanear Z6which overhangs thereset drive ratchet 66. A tail portion 78 of the clutch dogbears-against a spring extension 30 of a formed sheet-.springmember $2(see-also Fig. 2-). This spring member is riveted to the opposite sideof the stop disc 70 from the dqgfiz and-its spring; extension 80 extendsthrough an elongated slot 84 of the stop disc. By the spring extension80 the pivoted clutch dog is urged in eloclgwisedirection, tendingto;engage the reset drive ratchet 66. However, the clutch dog isnormally held disengaged by a trigger 86 pivoted at 88 on a bar 97 whichis rockably mounted on a stationary pin 93 projecting rearwardly fromthe front plate 10. A spring 100 urges the trigger counterclockwise onits pivot, so that an ear 105 of the trigger rests on the bar 97. Thetrigger is also provided with an arm 90 (Fig. 4) extending rigidlyrearward from the trigger acrossthe path of an arm 92 on the clutch dog.The stop disc is held forward in the latched position by a squareshouldered detent 94 on a lever 96 pivoted at 98 in the frame plates andurged clock; wise by a spring 99. The detent bloclc94 engages in a notchr the disc 70, while a pin 103 on the lever 96 engages in a notch ltliof the bar 97 to determine the position of the latter. If the trigger 86rocked slightly clockwise to release the arm 92, in a manner to bedescribed presently, the clutch dog is released and engages the contnuously running reset drive ratchet 66.

, The'stop. disc 70 starts a rotation at the rate of i R. .P. M. withthe ratchet 66 The detent block 94 is cammed out of notch 95, rockingclockwise the 9" and moving the trigger 86 slightly forward to theposition shown in Big. 3. The trigger remains in the slightly forwardposition shownin Figj while the detent 1 10a; 94 rides on the peripheryofustopadisc 7.0. Atthe end of the revolution of,the stop disc thedetent block 94 drops into the notch v95 suddenly, just as tail 92 .ofthe clutch dog arrives in front of. the arm 90. bar snaps,counterclockwise ,and the arm 90 strikes the tail 92 .of the clutch(10%,. knockingthe latter out of engagement with the ratchet disc. 66..

I Revolvably mounted on.-the shaftW68 adjacent -stop disc.70 is aslotted disc 102, which=may be called the minute hand setting -discfThis disc has fixed to it a gear 104 which meshes with the gear 56. Theslotted disc 102 is thereby driven at the normal rate of one revolutionper hour. 6 The spring plate niember 82 has a spring arm 106th e end ofwhich stands outward against the disc 102, for coaction with a slot 108therein.

When the clock is on time the slot 108 and the spring arm 106 have thepositions shown in Fig. 1 at the time a correction signal is received.When the clutch dog 72 is engaged the stop disc 70 makes a revolution inone minute, the end of the spring arm 106 traveling in clockwisedirection in a circle and bearing upon the disc 102. By the time thespring arm 106 has completed this circuit the slot 108 has moved down toa position such that the end of the spring arm just comes into contactwith the lower edge of the slot as the stop disc 70 is latched up. Onthe other hand, if the clock is slow the slot 108 will be at some higherposition than that shown in Fig. l and the end of the spring arm 106will engage the lower edge of the slot and move the disc 102 forward atthe rate of 1 R. P. M., instead of the rate of 1 revolution per hour, atwhich it is driven by the normal clock gearing. This accelerated motionof the disc 102 is transmitted through the gears 104, 56 and 54 to theminutes shaft and through the gears 58 and 60 to the hours shaft,restoring the minutes and hours hands to correct time.

The correction signal is received by a correction magnet 110 mounted byits yoke 112 and ears 114 upon the frame plate 12. An armature 116 ismounted on the yoke 112 by its pin 118 engaged by a spring 120. An arm122 of the armature carries at its upper end a pivot pin 124 on which ismounted a toothed rocking sector 126. When the magnet 110 is energizedthe armature rocks clockwise and the toothed sector 126 engages thecontinuously rotating reset drive ratchet 66, being rocked thereby incounterclockwise direction in Fig. 1. If the toothed sector 126 is heldin engagement with the toothed disc 66 for a period of say 3 seconds ofcontinuous signal an arm 128, called the delay cam, rigidly butadjustably connected to the toothed sector, is raised far enough toengage arm 90 of the trigger 86. Thereby the trigger is lifted and theclutch is released for engagement.

12 hour correction The mechanism described so far is rather similar tothat disclosed in the above-mentioned Larrabee patent and is sufficientto correct the clock for errors within a single hour. In accordance withthe present invention means are provided to enable the same mechanism tobe used for correction of the clock for greater errors. By theadditional means now to be described errors up to 12 hours can becorrected.

The trigger 86 has a tail 132 which extends parallel to a reset latch inthe form of a spring plate 134. This reset latch is fixed to a shaft 136rockably mounted in the side plates 10 and 12. The reset latch is pulledby a spring 137 so that a roller 139 on its lower end rests against thestop disc 70. With the latch plate in this position the movement of thetrigger 86 by the delay cam 128 is not sufiicient to make its tail 132pass over the end of a lug 138 and become latched thereby. However, whenthe stop disc is turning in response to a correction signal and thenotch 95 allows the roller 139 to move to the left (see Figs. 2 and thelug 138 moves to the right and a movement of the trigger 86 by the delaycam in response to a signal at this time will cause the tail 132 tolatch behind the lug 138. When this occurs the trigger 86 will not bemoved to release the clutch dog at the end of one revolution, but willremain clear of the clutch dog arm 92 until the trigger is released fromthe lug 138. In this way the slotted disc 102 can be made to rotatecontinuously for a plurality of revolutions by the stop disc 70 and thespring arm 106, driving the minute and hour hands forward through acorresponding number of hours.

The latch plate 134 is flexed to release the tail 132 of the trigger 86by a so-called 12 hour latch reset arm 140 pivoted on a fixed pin 142 onthe frame plate 10. The arm 140 is normally held by a spring 144 againsta stop 146. Its lower end 148 extends leftward into the path of a pin150 on the gear 60 which is fixed to the hours shaft 26. As the pin 150travels around it cams the reset arm 140 counterclockwise (Fig. 3),causing its upper end to deflect the latch plate 134 backward, bycamming against an outstanding lug 152.

The operation of the device will now be described with reference to thecircuit diagram shown in Fig. 1, also to the operational views shown inFigs. 2, 3 and 5.

Fig. 1 shows the circuit of magnet powered by a battery 154 andcontrolled by the following cams:

1. Cam 156, which closes its contact 158 once an hour at 59' 30" andopens it at 60' 30".

2. A cam 160, which transfers its contact spring to close contact 164 at11 oclock, 55 minutes, each 12 hours and transfers the contact springback to close contact 162 at 12 hours 5 minutes. These contacts thusremain in the position shown for all but the 10 minute period from 11:55to 12:05 of each 12 hours.

3. A cam 166, which closes its contact 168 from 55 seconds to 60 secondsof each minute.

4. A cam 170, which closes its contact 172 from 55 seconds to 60 secondsof each minute.

5. A earn 174, which closes its contact 176 from 31" to 36 each minute.

With the contact 162 in its normally closed position, at 59' 30" of thehour contact 158 closes, preparing a circuit which will be closed bycontact 168 at 55 seconds of that minute, to the correction magnet 110.The correction magnet will remain energized for five seconds, a periodlong enough to trip the trigger 86. The stop disc 70 will thus gothrough one cycle and will be latched up at the end of one minute. Thiswill correct the clock for slowness up to one hour.

At 11 hours 55 minutes contact 164 closes and contact 162 opens. At 5930" after 11 contact 158 prepares a circuit which is completed by theclosure of contact 172 at 55 seconds. This contact remains closed for 5seconds, causing the trigger to be lifted and the clutch to be engaged.At 12:00 31 contact 176 closes and another 5 second signal is sent tothe magnet 110. The delay cam begins to rise and about 4 seconds laterreleases the trigger. At the same time, 00' 35", the roller 139 dropsinto notch 95 and the latch 134 is moved slightly counterclockwise,shifting lug 138 a little to the right. In this position of the lug 138the tail 132 of the trigger is latched behind it, as shown in Figs. 2and 5.

Let it be assumed, now, that the clock is one hour, 20 minutes slow, dueto power outage. The pin 150 is slightly above the position shown inFig. 1. The spring arm 106 engages in the slot 108 and brings the clockinto a position within one hour of correct time at the end of the firstrevolution of the stop disc 70. The clutch dog is not disengaged by thetrigger 86, which has been latched up by the time the clutch dog passesthe trigger arm 90 on its first revolution. After this pin 150 earns thereset arm and deflects the latch plate 134, releasing the tail oftrigger 86. The trigger drops onto bar 97. At the end of the secondrevolution of the stop disc 70 detent block 94 drops into notch 95 andthe clutch dog is disengaged. The clock has been restored to within oneminute of correct time, the lateness of one minute which remains beingdue to the fact that the correction for more than one hour took an extraminute. In fact, the number of minutes which the clock will remain slowafter the 12 hour correction will depend upon how many hours the clockwas slow when the 12 hour correction signal was received. At 12:05 thecam 160 transfers the contact 162 to closed position and the next hourlycorrection signal through contact 168 will restore the clock to correcttime.

If the hour hand of the clock is on time when the 12 hour correctionsignal arrives the latch 134 will be in the rearwardly deflectedposition, pin being against the end 148 of lever 140. The lug 138 willtherefore not be in position to latch the tail of the trigger and thecorrection means will respond as for an hourly correction signal. 7While there have been shown and described and pointed out thefundamental novel features of the invention as applied to apreferredembodiment, it will be understood that variousomissions andsubstitutions and changes in theform and details of thedeviceillustrated and in its operation may be made by those skilled inthe art, without departing from the spirit of the invention his theintention, therefore, to be limited only as indicated by the scope ofthe following claims.

What is claimed is:

1. In a clock, minute and hour indicators geared together in a twelve toone ratio, means for driving said indicators at normal time rate, andregulating means for said indicators comprising reset driving meansincluding a clutch to drive the same at an accelerated rate, means toarrest said reset driving means when said minute indicator arrives at apredetermined time indication, including a trigger for disengaging saidclutch, latch means to hold said trigger in an ineffective position, andmeans including an element moved synchronously with said hour indicatorfor releasing said latch and restoring said trigger to effectiveposition when said element reaches a particular one of all of itspossible positions.

2. In a clock, minute and hour indicators geared together in a twelve toone ratio, means for driving said indicators at normal time rate, arotary element geared to said minute indicator having a radial engagingedge thereon; regulating means including a rotary member having means toengage said edge, driving means to turn said rotary member in adirection to drive said indicators forward at an accelerated rate,clutch means to couple said driving means to said rotary member, andmeans urging said clutch means toward engagement; trigger means normallyholding said clutch means disengaged, signal responsive means to releasesaid trigger means from said clutch means, means to cause said triggermeans to disengage said clutch at the end of a revolution, means tolatch said trigger means in ineffective position, means responsive to aparticular signal for causing said trigger to be latched by said latch,whereby said rotary member is made to execute more than one revolution,and means including an element moved synchronously with said hourindicator for releasing said latch means and allowing said trigger meansto be restored to clutch disengaging position when said element reachesa particular one of all of its possible positions.

3. In a clock having minute and hour indicators geared together in a 12to 1 ratio, means to correct the setting of said indicators for errorsgreater than one hour, comprising means to drive said minute indicatorat an accelerated rate for a plurality of 60-minute cycles, meansincluding an element moved in a fixed simple ratio to said minuteindicator for terminating said accelerated drive when said elementreaches a predetermined position, and means including an element movedsynchronously with said hour indicator for delaying the action of saidterminating means until said second mentioned element reaches aparticular one of all of its possible positions.

4. In a clock having minute and hour indicators geared together in a 12to 1 ratio, correction means to drive said minute indicator at a rategreater than the normal time rate for a plurality of 60-minute cycles,means to terminate the drive of said minute indicator by said correctionmeans when said minute indicator reaches a predetermined indication,means adapted to be controlled by a correction signal for rendering saidterminating means inoperative for a plurality of 60-minute cycles ofsaid minute indicator, and means including an element movedsynchronously with said hour indicator for restoring said terminatingmeans to effective position during a partic ular one of said 60-minutecycles.

5. In a clock having a plurality of time indicators geared together tooperate at a predetermined rate ratio, means g Sald rndica al e for d lnst t a cei at gate e;

a r ra it-yi .cycl swt. sai sh n tej, i

6. Correcting means for a clock having minute and hour indicators gearedtogether in a twelve to one ratio, comprising correction drive means,means including a clutch for coupling said correction drive means tosaid minute indicator, said correction drive means being adapted todrive said minute indicator at a rate many times faster than the normaltime rate, disengaging means for said clutch adapted to operate whensaid minute indicator reaches a predetermined position in any cycle, andmeans including an element moved synchronously with said hour indicatorfor delaying the operation of said disengaging means through a pluralityof cycles of said minute indicator, until said element reaches apredetermined position.

7. Correcting means as described in claim 6, wherein said clutchdisengaging means is adapted to be conditioned to release said clutchfor engagement for a single cycle or for a plurality of cycles undercontrol of said delaying means.

8. In a clock, a timekeeping mechanism including minute and hourindicators, means to drive said minute indicator normally at the rate ofone minute step indication per minute, driving means interconnectingsaid indicators whereby said hour indicator is normally advanced onehour step indication per hour, correcting means to drive said indicatorsat an accelerated rate, including means to terminate the accelerateddrive of said indicators when said minute indicator arrives at apredetermined position in any cycle, and means to control the number ofcycles of operation of said minute indicator by said correcting meansbefore said terminating means is operated.

9. In a self-regulating clock system comprising a master clock, asecondary clock having minute and hour indicators geared together in a12 to 1 ratio, and a signal channel interconnecting said clocks; meanscontrolled by said master clock for transmitting over said signalchannel to said secondary clock two differentiated types of signals, onetype every hour and the other type every twelve hours; and correctingmeans in said secondary clock comprising means for driving said minuteindicator, and thereby said hour indicator, many times faster thannormal speed; means responsive to an hourly type signal for engagingsaid correcting means for a single cycle to drive said minute indicatorto a predetermined position, said last means being responsive to a12-hourly type of signal to engage said correcting means for a pluralityof cycles; and means including an element moved synchronously with saidhour indicator for determining the number of cycles during which saidcorrecting means remains engaged, the disengagement of said correctingmeans being timed to occur when the minute indicator arrives at saidpredetermined position.

10. Clock correcting means as described in claim 9, characterized by thefact that said hourly type signal comprises a single pulse While said12-hourly type signal comprises two distinct pulses, said means forengaging said correcting means including a trigger and a latch devicetherefor, and means for moving said trigger each time a signal pulse isreceived, a latch device normally out of position to latch said triggerwhen moved in response to a signal pulse, and means to move said latchdevice between the first and second pulses of a 12-hourly signal to aposition to latch said trigger when it is moved in response to saidsecond pulse.

11. In a clock, minute and hour indicators geared together in a normalratio, means for driving said indicators at normal time rate, andregulating means for said indi 7 cators including reset driving means todrive the same reenabling said arresting means when said last mentionedat an accelerated rate, means including an element moved element reachesa certain one of all of its possible posiin a fixed simple ratio to themovement of said minute tions. indicator for arresting said drivingmeans, said arresting means being operable during any revolution of saidminute 5 References Cited in the file of this patent indicator to arrestsaid reset driving means when said UNITED STATES PATENTS minuteindicator arrives at one certain position, means 1,016,499 Hickok 6 1912to disable said arresting means for one or more revolu- 2,145,018Tweedale Jan. 1939 tions of said minute indicator, and means includingan ele- 2,167,829 Panel. 1939 ment moved synchronously with said hourindicator for 10 2,569815 Larrabee Oct 2, 1951

